Re: [PATCH v7 02/15] sched/core: uclamp: Enforce last task UCLAMP_MAX

On 13-Mar 15:12, Peter Zijlstra wrote:

On Fri, Feb 08, 2019 at 10:05:41AM +0000, Patrick Bellasi wrote:

quoted

+static inline void uclamp_idle_reset(struct rq *rq, unsigned int clamp_id,
+				     unsigned int clamp_value)
+{
+	/* Reset max-clamp retention only on idle exit */
+	if (!(rq->uclamp_flags & UCLAMP_FLAG_IDLE))
+		return;
+
+	WRITE_ONCE(rq->uclamp[clamp_id].value, clamp_value);
+
+	/*
+	 * This function is called for both UCLAMP_MIN (before) and UCLAMP_MAX
+	 * (after). The idle flag is reset only the second time, when we know
+	 * that UCLAMP_MIN has been already updated.

Why do we care? That is, what is this comment trying to tell us.

Right, the code is clear enough, I'll remove this comment.

quoted

+	 */
+	if (clamp_id == UCLAMP_MAX)
+		rq->uclamp_flags &= ~UCLAMP_FLAG_IDLE;
+}

-- 
#include <best/regards.h>

Patrick Bellasi